The main aim of this book is to teach the Arduino IDE and Micro-Python programming languages in ESP32 based projects, using the highly popular ESP32 DevKitC development board. Many simple, basic, and intermediate level projects are provided in the book using the Arduino IDE with ESP32 DevKitC. All projects have been tested and work. Block diagrams, circuit diagrams, and complete program listings of all projects are given with explanations. In addition, several projects are provided for programming the ESP32 DevKitC using MicroPython. The projects provided in this book are designed to teach the following features of the ESP32 processor: • GPIOs • Touch sensors • External interrupts • Timer interrupts • I2C and I2S • SPI • PWM • ADC • DAC • UART • Hall sensor • Temperature sensor • Infrared controller • Reading and writing to SD card • Reading and writing to flash memory • RTC timer • Chip ID • Security and encryption • Wi-Fi and network programming • Bluetooth BLE programming • Communication mobile devices • Low power design • ESP-IDF programming The projects have been organized with increasing levels of difficulty. Readers are encouraged to tackle the projects in the order given. A specially prepared hardware kit is available from Elektor. With the help of this hardware, it should be easy and fun to build the projects in this book.